Drop bottom mine car



Feb. zo, 1951- R. A. SHIELDS m; 2,542,437

DROP BOTTOM MINE CAR ATTORN EY sr me w 2 n 4 .L M WBK@ S O T 2 m mlcm m .Isc S l` r 3. ee 1% HRM f L m.. m QQ W DM am IT HT Sm Aw R R.D

Feb. 2o, 1951 Filed Aug.

Feb. 20, 1951 R. A. sHlELDs ETAL DROP BOTTOM MINE OAR 3 Sheets-Sheet 3 Filed Aug. 29, 1946 ATTORN EY Patented Feb. 20, 1951 onor BoTroM MINE CAR.

Robert A. Shields and Robert C. Kepner, Bloomsburg, Pa., assignors to AmericanCar and vFoundry Company, New York; N; Y., ax corporation of New Jersey Application August/29, 19.46, `Serial No. 693,743.

19 Claims.

This invention relates to mine cars in general and in particular to drop bottom cars in which the doors are hinged to swing about transversely extending axes.

The majority of drop bottom mineA cars built heretofore have had their doors so interconnected and related as to cause the rear door to open first, with the result that the 'coal carried by the forward door will have to drop a considerable distance into the receiving bin or hopper, with the `result that considerable breakage occurs. It is well known that the finer the coal, the lower its cost and accordingly any excessive breakage of coal results in large losses of revenue to the operator. Certain types of drop bottom cars have been made which will partially overcome this disadvantage of excessive coal breakage. These cars unlatch in exactly the same order as the cars previously referred to but have their partsV so related that the doors need drop through an angle of but roughly twelve degrees in order that the .fortan-rd wil-l be unlatchedlor dumping into the hopper. With the doorsdropping through approximately twelve degrees, it is obvious that excessive spillage of coal over the rear ends of the doors may occur. It will also be obvious that in most instances considerable spillage of coal can occur over the side edges of the doors `and beneath the side sill. Suchspilled coal gradually builds up and will eventually prevent proper operation of the car doors. Furthermore, the grinding action of the doors sliding on this'spilled coal increases the percentage of fine coal with considerable loss to the operator. It is an object,

therefore, of the present invention tov provide ai* drop bottom mine car in which the doors may be unlatched by a single means and all conditioned for openingl at the time the door has dropped a distance substantially equal to the l height of the rail.

A further object of the invention is the provision of a drop bottom mine car in which the doors automatically unlock from rear to front and without dropping the side edges sufficiently below the lower edge' of the side sills as to permit'` Fig. 2 is a rear end View of the car withlporvtions'broken away to better disclose the construction;

Fig. 3 is an enlarged plan view showing the ldetails of construction adjacent the door hinge;

Fig. #i is a plan view of the rear end of the car;

Fig. 5 is an enlarged sectional View similarto Fig. 1 and showing the two rear doors in closed position;

Fig. 6 is a sectional view similar to Fig. 1 but showing the two rear doors in preliminary dropped or unlatched position;

Fig. 7 is a sectional view showing 'the rear door in fully open position;

Fig. 8 is an enlarged sectional view showing a slight modification and with the doors in raised position such as in Fig. 5;

Fig. 9 is a plan view of the arrangement of Fig. 8, and

Fig. 10 is a sectional view of the modification of Fig. 8 and with the doors shown in preliminary dropped position as in Fig. 6.

Referring now to the drawings in detail, it will be seen that the car is" formed of sloping side wallsS connected to side sills 8 and suitably braced by gussets It. The side sills are connected together by a rear end sill and buffer construction R and a forward bumper and end sill construction F. Also, the sloping side walls are connected together by front and rear end walls I2 and I4 respectively and these end walls are in turn connected to the bumper and end sill structures in the customary manner. The side sills are pierced as at i6 to receive axles A which are supported by wheel W running on rails or other structure, the top surface of which is indicated at 2li. The wheels in most instances will Aproiect through the sloping side wings or floors li4 and will be covered by wheel housings (not shown) and these wheel housings as well as the side sillswill be tied together transversely of the car by axle housings 22, which housings protect theaxles A as well as the hinged joint between the car doors.

The car as shown is provided with three doors, namely, a forward door i, an intermediate door 2 and a rear door 3. The forward door I is hinged directly to a rod or other means 24 supported by the side sills and this rod is mounted beneath a portion of the forward end sill structure so as to prevent leakage of coal at the hinged edge of this door. The intermediate door 2 and rear door 3 have their forward ends rolled over as at 23 in order to rotatably engage hinge rods 33. These rods have their ends welded or otherwise secured to strut members 32 carried adjacent each side sill and with their lower ends rounded and adapted to bear on a support member 34 riveted, welded or otherwise secured to the side sills. The strut members 32 are held in position by means of bolts or other devices 36 (Fig. 2) extending through the support, side sill and portions of the axle box 40. As clearly shown in the figures each support member 34 is carried adjacent to but forwardly of an axle A and has the portion remote from the axle provided with an upwardly and forwardly inclinedY surface 42 (Fig. 6) against which the strut member 32 is adapted to strike, thereby controllingr the movement of the strut members and connecting hinge rod toward the forward end of the car. Each of the strut members is provided with a flattenedV surfaeells adapted to strike against the axle A or similar structure, thereby limiting the rearward movement of the struts and connecting -hinge rod. As clearly shown, particularly in Figs.

bottomlplates 53 to the side edges of which are welded or otherwise secured vertically extending side plates 52, The side plates of forward door I canextend straight to the hinge axis of the door but the side plates of doors 2 and 3 must be offset as at 513 (Fig. 3) in order to clear the cranked ends of its hinge. The slight space appearing between the side sills and the side of the door at the hinges will, of course be protected by the axle housings previously referred to. The rear edge of rear door 3 has attached thereto a latch tongue Si) adapted to be engaged by a hook 32 carried by an operating arm 34 pivotally mounted on the end structure ofthe car and extending laterally toward the side of the car for engagement by a trackside ramp (not shown).

The rear end structure Ialso has pivotally .mounted thereon swinging pushers 65 which are VVand by the cranked hinge of door 2. Door 2 willV in turn be held in raised position by means of its own hinge rod 30 and the cranked hinge rod of door 3 with any accidental shifting of door 2 being prevented by the stop 46 carried on the roll of door 3 and byinclined surface 42' of support member 34 for door 2. Door 3 will be held in raised position by its hinge rod 30 and by the hook 32 carried on the end structure of the car. It is to be noted that the strut members 32 form- -ing the cranked ends of the hinge rods are so supported when the doors are in raised position that the axes of hinge rods 30 are forwardly of the vertical line through the point of support for the strut members. In this manner the Ypressure of load on the doors will tend to hold Vthe doors in their forwardly shifted position. The'degree of inclination of the strut members 4 is so chosen as to normally support the doors in a stable condition. When the loaded car reaches the dumping station the trackside ramp will lift the operating arm Sli and cause the hook 62 to disengage from the tongue 6l). This will permit the rear edge of door 3 to drop to the line and dash position of Fig. by merely rotating around its hinge rod 30. In this position the doors will be supported on the top surface of the ties or some similar structure located between the rails and indicated at l2 in Figs. 5 and 6. With the door in this position resting on the surface 12, it will be seen that the side edges 52 are never suiliciently below the lower edge of the side sills as to permit spillage of lading over the side edges of the door. Continued forward movement of the car will cause the strut members 32 to rock about their lower ends until the flat surface lill strikes the axle and limits further movement.

The door will then be in the full line position of Fig. 6 and it should be noted that both in its preliminary position shown by line and dash of Fig. 5 and full. line of Fig-6 the rear end is sufficiently close to the end structure as to substantially vprevent spillage of lading over the rear edge of the door. With the door 3 inthe full line position of Fig. 6 the rear edge of door 2 will be'out of engagement with the forward edge of door 3 and accordingly it may drop .onto the surface 'I2 with the'forward movement of the car rocking its strut members 32 until they strike the forward axle as a stop, thus releasing the forward door l for dropping into the pit or hopper. Continued forward movement of the car will, of course, allow door 2 to move off of the supporting surface I2 and open into the lading receiving hopper and in the same manner door 3 will move olf the surface and can swing into the hopper to its full open position for complete discharge of the load. In other words,V the'doors will be unlatched in a 3-2-1- order but will discharge their load into the hopper` in a 1-2-3 order. As is customary when the car reaches the far end of the dumping hopper, the door l will engage a ramp and be raised slightly above its normal closed position.V Likewise, doors 2 and 3 will be raised into positions slightly above their true position. Raising of doorV 2 by the ramp will cause its free edge to engage the under side of door 3, vthus throwing the cranked hinge rod of door 2 forwardly and permitting the free edge of door 2 to clear the hinge rod of door 3 irrespective of the position of door 3 hinge rod. Raising of door 3 to its nal position will cause its free edge to engage fingersY 33 of rotating pushers 66. As these members are rotated to their full line position of Figs. 1 and 5 they will push door 3 forward beneath the free edge of door 2 and hold the same in raised position. If for any reason door 2 is notA in its forwardly shifted position, the stop 46 carried on the-roll of door 3 will force door 2 forwardly under door I to hold it in raised position. It is, of course, obvious that when door 3 has been fully raised the hook52 will automatically engage tongue 50 and hold the door in raised position. As shown, the axesof the hinge rods 30 for doors 2 and 3 will be rearwardly of a vertical plane through the vpoints ofV support for struts 32 whenever the sition shown in Figs. 6 and 7, but this placement of the axes rearwardly of the vertical plane under these conditions is not as important as the placement of the axes forwardly of the vertical plane through thev supportati struts; 3.2

when the doors are` in closed position aspreviouslyv referred to.

It. will be obvious that while the doors as mounted-.will open ina l'23 order into the hopper, a rearrangement' of the tripping ramp will permit the doors to open ina customaryr 3--2-1 orderthus the car may be used for either type of service and without change. Under such oircumstances it becomes impossible to use a relatively long closing ramp such as might be needed for the form of door shown in Figs. 1 to-7 and whereshort closing ramps only cani used the modification showin in Figs. 8, 9 and 10 will be particularly adaptable. ln these'figures since so many parts are identical in shape, form. and operation to thoseof the saine parts in Figs. 1 to 7, the same reference numerals have been used wherever possible. In this slight modification the stop it has been moved from the roll of door 3 to the strut members 32 as is indicated at Bt. This stopserves the saine function as does the stop it in that it prevents accidental rearward shifting of door 2 while at the same time pushing door 2 forwardly in case it is out of place slightly when door 3 is closed. In order that. each of the doors 2 or ii may close properly and of itself rock the strut members 32 forwardly under the next forward door a bar member S2 has beenwelded or otherwise attached to the strut members 32 and these bar members extend inwardly sufficienti far to overlap the door plate and engage a spring or other resilient member i3d attached as at 3b to the door. While the spring or resilient member has been; shown as attached to the door and the rigid member to the strut, it is obvious that their positions may be interchanged or that rubber or other elastic material can be substituted for the spring shown. In cases where the resilient member is car 'led by the struts 32 it wouldbe prefer able that the bars iii' be made of spring Steel and Yextended completely across the door so as to be struck adjacent the center by a projection on the door.

insofar as the operation of the doors and cranked hinges are concerned it will be identical with that described inconnection with Figs. l to 7. In this iorm, however, when the doors either 1i or 22 drop downwardly onto the surface i2 they will rotate around the hinge rod 3o tending to bring spring Bil and bar 82 out of contact. As the irictional drag of the door 2 or 3 pulls, the hinge rods rearwardly the door will in effect rotate in a clockwise direction on its hinge rod as viewed in Fig. 8, this movement being due to the fact that the strut members are rocking rear wardly while the door is held from rotation by its contact with surface 12, This rocking movement of the strut members from the position of Fig. Sito that of Fig. will, of course, be permitted due to the compression of tlie'spring and since the irictional drag or" the loaded dooron the surface i2 will be much larger than the. frictional drag of the empty door, it will be. seen that the spring will be compressed permitting release of the next forward door. During closing movement of the doors by the track-side ramp (not shown) the door will be swung freely about its hinge rod 3l) until the spring its comes into contact with stop member 82. Continued upward movement of the door will compress the spring 8d until suiiicient energy is stored therein to oiiset the frictional drag of the empty door on the closing ramp. As soon as sufficient energy has been stored in the spring it will either throwtheizstrut `nrenmersSZ forwardly or willcausefthestrutmeme bers tdroclr: forwardly about. theirv lower ends duringfcontinuedclosing movement of the door. mother. words,.the rst closing movement of the door will befby-free rotation around. its hinge rod, thenv after sufficient compressionzhas been placed inthe springifurther rotation of the door will taire place by the rocking of the entire door and crankedihihges about thelower ends of the strut members 32.. Thus each of the doors which is mounted onta cranked hinge is so constructed as tosof; itself roclr forwardly beneath the forn ward door during itsiinal closing movements. In this manner a short closing ramp can be used sincef itisinot; necessary to hold all ci the doors closed'. until the latch at theV rear end of the car isengaged.

While thecar has been described with specic `.referencesitoV the drawings and reference has been `made to. certain modiiications it will be obvious .th'attotherV modifications may be made without departingfrom the scope of the invention. as de riediby the. following claims.

What is claimed:

l.. Ina dropibottom mine car, the combination of a bottom door normally retaining lading in the car and swingable to an open position for discharge of lading, hinge means providing a first axison. which said doorc'an swing between open `and closed positions, and means supporting said hinge inean'sand providing a second axis located belowfsaid first exis about which said hinge means oscillate.

2. In a drop bottom mine car, the combination of! a bottom door normally retaining lading in thecar and swingable to an open position for discharge of lading', hinge means providing a first axis onwhich said door can swing between open and'closed-positions, strut means supporting said hingev means for oscillatory movement about a second axis located below said rst axis, and means limiting said oscillatory movement to maintain said axes in the relationship stated.

3; In a drop bottom mine car, the combina `tion of a bottom door normally retaining lading .means supporting said hinge rod for oscillatory movement longitudinally of the-car, and means securedfto the'car and providing a support for lsaid strut means below said hinge rod.

4: Inra drop bottom mine car, the combination or' a. bottom door normally retaining lading in the car and swingable toA an open position for discharge of lading, a hinge rod extending transversely of the car and on which said door may swing between open and closed positions, strut means supporting said hinge rod for rocking movementV longitudinally of the car and about an axis locat-edbelow said hinge rod, and means limiting the rocking movement of said strut means, said strut means and last named means being so constructed and arranged as to permit substantially equal rocking movement to either sideoi a vertical plane through said axis.

5. In a drop bottom mine car, the combination of' a bottom door normally retaining lading in the car and swingable to an open position for discharge of lading, a hinge rod extending transversely of the car and on which said door may Vswing between open and closed positions, strut means supporting said hinge rod for rocking axis located below said hinge'rod, and means associated with said door and strut means and limiting relative movement therebetween.

V6. In a drop bottom mine car, the combination of a bottom door normally retaining lading in the car and swingable to an open position for discharge of lading, a hinge rod extending transversely of the oar and on which said door may swing between open and closed positions, strut means supporting said hinge rod for rocking movement longitudinally of the car about an axis located below said hinge rod, and means secured to said strut means and door and limiting relative movement therebetween.

'. Inv a drop bottom mine car, the combination.

of a bottom door normally retaining lading in the car and swingable to an open position for discharge of lading, a hinge rod extending transversely of the car and on which said door may swing between open and closed positions, strut means supporting said hinge rod for rocking movement longitudinally of the car about an aXis located below said hinge rod, and means secured to said strut means and door to limit relative movement therebetween, said means including resilient devices controlling certain of the rela- Vtive movements between the strut means and door.

8. In a drop bottom mine car, a body having sills Vsupported 'axles located between the upper and lower edges of the sills, drop bottom doors swingable between the sills, hinge rods supporting the doors for swinging movement about an axis located substantially in the horizontal plane of the axles, and strut means supporting certainof said hinge rods for rocking movement longitudinally of the car about axes 10, In a drop bottom mine car, a body having i sills supported by axles located between the upper yand lower edges of the sills, drop bottom doorsk swingable between the sills, hinge rods supporting the doors for swinging movement about an axis located substantially in the horizontal plane fof the axles, strut means supporting certain of said hinge rods for rocking movement longitudinally of the car, and means connected to said sills adjacent their lower edges and providing supports for the lower ends of said strut means, said means including stops limiting the rocking movements of said strut means in at least one direction. s

ll. In a drop bottom mine car, a body supported on axles located above the lower edgeof the body, a drop bottom door swingable longitudinally of the body, a hinge rod supporting the door for swinging movement thereon and located above the lower edge of the body, said hinge rod having cranked ends supported on the body adjacent the lower edge thereof, and means limiting movement of the cranked ends whereby said hinge rod may have limited rocking movement` longitudinally of the car. Y

12. In a drop bottom mine car, a body, a rear ldrop bottom door swingable longitudinally of vthe body, a second drop bottom door swingable longitudinally of vthe body and normally having its rear edge resting on the forward edge of said rear door, a hinge rod supporting the forward edge of said rear door and upon which said door Y may swing, cranked ends on said hinge rod extending when the door is closed downwardly and rearwardly therefrom toV pointsV of support on said body whereby said hinge rod may rock longitudinally ci the body independently of the swinging movement of the rear door upon said hinge rod, and latch means holding said rear door in raised position and preventing longitudinal rooking of said hinge rod.

13. In a drop bottom mine car, a body, a rear drop bottom door swingable longitudinally of the body, latch means normally holding said rear door in raised position, a'second drop bottom door swingable longitudinally of-the body and normally having its rear edge resting on the forward edge of said rear door, a hinge rod supporting the forward edge of said rear door'and upon which said rear door may swing, cranked ends on said hinge rod extending downwardly therefrom to points of'support on said body and serving as struts supporting the hinge rod, said cranked ends being free to rock about their points of support after a slight drop of the rear edge f bottom door swingable longitudinally of the body between open and closed positions, latch means normally holding said door in closed position, a hinge rod supporting the forward edge of said door and about the axis of which said door may swing, cranked ends on said hinge rod extending downwardly therefrom to points of support on said body, said cranked ends rocking on said points of support between an upwardly and forwardly inclined position when the door is closed and an upwardly and rearwardly inclined position when the door is open.

l5. In a drop bottom mine car, a body, a drop rbottom door swingable longitudinally of the body between open and closed positions, latch means normally holding said door in closed position, a hinge rod supporting the forward edge of said door and about the axis of which said door may swing, cranked ends on said hinge rod extending downwardly therefrom to points of support on said body, said cranked ends rocking on said points of support from a Vnormal upwardly and forwardly inclinedposition to an upwardly and rearwardly inclined position upon a slight swinging movement of the door followingV release of said latch means, and means engaging said cranked ends to limit the inclining movements thereof.

15. In a drop bottom mine car, a body, a drop bottom door swingable ongitudinally of the body -between open and closed positions, latch means normally holding said door in closed position, a hinge rod supporting the forward edge of said door and about the axis of which said doormay swing, cranked ends on hinge rod extending downwardly therefrom to points of support on said body, said cranked ends rocking on said pointsY of support from a normal upwardly and forwardly inclined position to an upwardly and rearwardly inclined positon upon a slight swinging movement of the door following release of said latch means, and coacting means on said door and cranked ends to move said cranked ends from their upwardly and rearwardly inclined positions to their upwardly and forwardly inclined positions upon closing movement of the door.

17. In a drop bottom mine car, a body, a drop bottom door swingable longitudinally of the body between open and closed positions, latch means normally holding said door in closed position, a hinge rod supporting the forward edge of said door and about the axis of which said door may swing, cranked ends on said hinge rod extending downwardly therefrom to points f support on said body, said cranked ends rocking on said points of support from a normal upwardly and forwardly inclined position to an upwardly and rearwardly inclined position upon a slight swinging movement of the door following release of said latch means, and coacting means on said door and cranked ends to move said cranked ends from their upwardly and rearwardly inclined positions to their upwardly and forwardly inclined positions upon closing movement of the door, said coacting means including resilient means.

18. In a drop bottom mine car, a body, an axle supporting the body, a drop bottom door extending forwardly beneath the axle, a hinge rod adjacent the axle and supporting the forward edge of said door, strut means supporting said hinge rod on said body at points located on the body beneath said hinge rod, latch means normally holding said door in raised position, said strut means being normally out of contact with the axle and rocking into Contact therewith upon a slight drop of the door following release of said latch means.

19. In a drop bottom mine car, a body, a drop bottom door swingable about a rst axis relative to the body, means mounting said rst axis for swinging movement about a second axis located below said rst axis, and means limiting said swinging movement to maintain said axes in the relationship stated.

ROBERT A. SHIELDS. ROBERT C. KEPNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Schroeder July 29, 1941 

